1. Field of Invention
The present invention relates to medical and surgical wound closure and management, and methods for making and using such devices. In particular, the present invention relates to medical and surgical wound closure and management, and related methods, where the tissue bonding article or wound closure device incorporates a polymerizable adhesive material applied to an initiator-loaded textile material. The materials and methods of the present invention provide an improvement over, and a substitute for, conventional bandages, sutures and staples, and provide improved methods for both approximating and covering and/or closing wounds, thus providing improved wound management.
2. Description of Related Art
There are currently in primary use at least four basic ways for closing wounds resulting from surgical incisions or accidental lacerations. These are sutures, surgical staples, surgical skin tapes, and adhesive compositions. Sutures are generally recognized as providing adequate wound support for the duration of wound healing. However, suturing involves additional trauma to the wound, as the needle and suture material must be passed through the tissue at the margins of the wound. In addition, suturing can cause cosmetically unattractive wound closure marks, can be time consuming, and, depending on techniques and types of sutures used, may require removal. Such removal entails further medical attention and can involve additional pain and trauma to the patient particularly if the sutures become embedded in the wound. In some cases, suture removal can require anesthetic, and can result in a railroad track appearance at the wound site.
Surgical staples have disadvantages similar to sutures in terms of cosmetic result. However, staples are generally believed to be even worse then sutures, at least in terms of the pain and trauma inflicted on the patient, and the resultant cosmetic appearance of the staple and wound marks. Further, removal of the staples can be painful and, depending on location and patient pain threshold, may require topical anesthetics.
Skin closure strips, such as conventional adhesive bandages, are utilized for closure of relatively superficial skin wounds, but their use is limited to only certain types and degrees of wounds. However, the contact adhesives that are used with such strips typically retain holding power for no more than a day or two and can lose holding power quickly in the presence of moisture, for example, perspiration.
Direct application of adhesives has also been proposed and used for wound closure purposes, especially involving cyanoacrylate adhesives. Such materials are achieving more widespread use for wound closure.
For example, monomer and polymer adhesives are used in both industrial (including household) and medical applications. Included among these adhesives are the 1,1-disubstituted ethylene monomers and polymers, such as the α-cyanoacrylates. Since the discovery of the adhesive properties of such monomers and polymers, they have found wide use due to the speed with which they cure, the strength of the resulting bond formed, and their relative ease of use. These characteristics have made α-cyanoacrylate adhesives the primary choice for numerous applications such as bonding plastics, rubbers, glass, metals, wood, and, more recently, biological tissues.
It is known that monomeric forms of α-cyanoacrylates are extremely reactive, polymerizing rapidly in the presence of even minute amounts of an initiator, including moisture present in the air or on moist surfaces such as animal tissue. Monomers of α-cyanoacrylates are anionically polymerizable or free radical polymerizable, or polymerizable by zwitterions or ion pairs to form polymers. Once polymerization has been initiated, the cure rate can be very rapid.
Medical applications of 1,1-disubstituted ethylene adhesive compositions include use as an alternate or an adjunct to surgical sutures and staples in wound closure as well as for covering and protecting surface wounds such as lacerations, abrasions, burns, stomatitis, sores, and other surface wounds. When an adhesive is applied, it is usually applied in its monomeric form, and the resultant polymerization gives rise to the desired adhesive bond.
For example, polymerizable 1,1-disubstituted ethylene monomers, and adhesive compositions comprising such monomers, are disclosed in U.S. Pat. No. 5,328,687 to Leung et al. Suitable methods for applying such compositions to substrates, and particularly in medical applications, are described in, for example, U.S. Pat. Nos. 5,582,834, 5,575,997, and 5,624,669, all to Leung et al.
Combinations of the above approaches have also been used in the art. For example, attempts have been made to combine the use of sutures or staples and adhesive compositions. See, for example, U.S. Pat. No. 5,254,132. Likewise, attempts have been made to combine the use of conventional bandages or tapes and adhesive compositions. See, for example, U.S. Pat. Nos. 5,259,835 and 5,445,597. However, these approaches have typically met the same issues as described above for the individual approaches, namely difficulties arising from the use of the sutures, staples and/or bandages or tapes.
Current approaches for combining the above wound closure approaches also include combining the use of adhesive compositions and bandage-like dressings. For example, U.S. Patent Publications Nos. 2002-0049503 and 2004-0106888 each disclose the combined use of adhesive compositions and mesh bandage-like materials. In each case, a mesh-like structure is applied to a wound, and an adhesive composition is applied to the mesh-like structure. When the adhesive composition sets, it bonds the mesh-like structure to the wound. In U.S. Patent Publication No. 2004-0106888, the wound dressing includes removable ends that adhere the mesh-like structure to the wound, but which can be removed after the adhesive composition sets, leaving the adherent dressing in place.
Commonly assigned U.S. patent application Ser. No. 10/779,721, filed Feb. 18, 2004, also discloses a combined adhesive composition and bandage-like dressing. The application discloses a tissue bonding article, comprising: a flexible material; an adhesive substance applied over at least a portion of a bottom side of said flexible material, for at least temporarily adhering the flexible material to a wound surface; and a polymerizable adhesive composition permeated throughout at least a portion of said flexible material. When the polymerizable adhesive polymerizes, the flexible material is adhered to the wound surface to provide an adherent composite dressing. The entire disclosure of this application is incorporated herein by reference.
A difficulty with these combined adhesive/flexible substrate approaches is in the application and polymerization of the adhesive composition. For example, where a polymerizable adhesive composition is applied to the substrate, the adhesive is either applied from an applicator device that includes a polymerization initiator, or the adhesive composition (which contains no initiator) is applied to the flexible substrate and wound site where polymerization is initiated by moisture or other fluids present at the wound site. In the first instance, polymerization of the adhesive composition is rapid, but the presence of the polymerization initiator in the applicator device creates a short working time, requiring that the adhesive composition be applied rather quickly. In the second instance, the working time of the adhesive composition is longer because the applicator device does not include a polymerization initiator. However, polymerization of the adhesive composition on the wound site is typically much longer and less consistent because polymerization relies upon weaker species (such as moisture or other natural substances present on the skin and not added specifically for polymerization initiation) that may be present in differing amounts.
Accordingly, a need continues to exist for improved materials and methods for wound approximation. A need also continues to exist for improved materials and methods that have a wider range of applications, from external to internal use, and from essentially non-biodegradable (where the materials are removed from the application site) to biodegradable (where the materials are not directly removed from the application site, but instead degrade over time).